According to a machine translation of the blog, the news came during a media event in Beijing, where Roger Capriotti, who leads IE marketing and often blogs about the browser, noted the impending launch of the preview.

Even so, Microsoft declined to confirm the launch, saying, "We do not comment on rumors or speculation."

Internet Explorer timetable

A Tuesday launch would fit with Microsoft's timetable in 2010 and 2011 for IE9. The beta of that browser launched Sept. 15, 2010, a day after that month's Patch Tuesday, while the final version debuted March 14, 2011, a day before that month's security updates.

Microsoft Patch Tuesday

Tomorrow is November's Patch Tuesday, the once-a-month delivery of security fixes by Microsoft.

Microsoft has declined to say when it expects to ship final code for IE10 on Windows 7, but if past practices are any clue, that could come as late as April 2013.

IE10 launched for Windows 8 and its tablet-oriented offspring, Windows RT, when those operating systems hit retail on Oct. 26.

Not usable by Win Vista or Win XP users

The browser, which Microsoft will deploy across all its OSes, including Windows Phone 8, does not support Windows Vista or XP on the desktop. Microsoft was the first, and so far, only, browser vendor to drop Vista from a support list, just as it was the first—and again, the only—developer to abandon Windows XP.

Like IE10 on Windows 8 and Windows RT, the version for Windows 7 will come with the "Do Not Track" (DNT) privacy feature turned on by default. The Windows 7 edition, however, will not include an integrated copy of Adobe's Flash Player, as does the one for Windows 8.

Although online advertising representatives have called Microsoft's unilateral decision to enable DNT "unacceptable," their tenor is likely to get even more vehement when IE10 on Windows 7 goes final. That's because Microsoft will automatically upgrade all Windows 7 users to the newest browser shortly after it launches.